- power transmission



July 18, 1944. c, MCKECHNIE POWER TRANSMISSION Filed Nov. 12, 1940 4 Sheets-Sheet l July 18, 1944. l. c. MCKECHNIE 2,353,840

POWER TRANSMISSION I Filed Nov. 12, 1940 4 Sheets-Sheet 2 i fgz 7 \Y! 48 /AP ATTO R N EYS.

I I v INVENTOR 1. c. MQKECHNIE POWER TRANSMISSION Filed Nov; 13, 1940 July 18, 1944. Y

flaw .1 ATTORNEY July 18, 1944- l. c. MCKECHNIE 2,353,840

POWER TRANSMISSION FiledNov. 12, 1940 4 Sheets-Sheet 4 I v -16; i

Fig.1

INVENTIOR BY v Ac u

Patented July 18, 1944 rowan TRANSMISSION Kan C. McKechnie, Detroit, Mich., assignor to Chrysler Corporation, Highland Park, Mich, a

corporation of Delaware Application November 12, 1940, Serial No. 365,223

26 Claims.

This invention relates to motor vehicles and refers more particularly to power transmission and control mechanism therefor.

In transmissions of the automatic or semiautomatic types, there is a tendency for the change speed mechanism to fail to operate properly after the transmission has been left standing in a cold atmosphere. Under such conditions the lubricants, to which the various parts are subjected, become "sticky and the parts tend to become sluggish in action if indeed they operate at all. various clearances between fits, connections, bearings, etc., throughout the mechanism and this results also in failure or improper operation of the transmission control.

In certain types of transmissions, such as disclosed for example in the copending application of Carl A. Neracher, et al., Serial No. 335,310, filed'May 15, 1940, failure of the automatically operating change speed control element to operate as intended may result in an undesired no- Also, very low temperatures afiect the back or lock-up condition in the transmission;

also in undesired and prolonged operation of the torque-relieving device which may comprise means for rendering the engine ignition system inoperative as by grounding the same. In addition such types of transmissions give rise to improper car starting speed ratios when the automatic speed ratio controlling mechanism fails to function properly. These troubles or failures are aggravated during very cold winter weather when.

the temperature falls below or Fahrenheit.

Especially are these troubles and failures experienced at temperatures below zero. Of course, after the car has been driving for awhile then the heat from the engine and friction heat throughout the mechanism raises the temperature of the parts so that they will function normally even though the atmosphere continues to remain at the very low temperatures mentioned.

his an object of my invention to provide means automatically responsive to temperature ruption, at times when the latter means tends to function improperly.

Another object is to provide thermal-responsive means for automatically controlling operation of one or more of the transmission speed ratio drives.

Another object is to provide improved means for guarding against the possibility of the transmission mechanism becoming locked-up or providing an undesired no-back condition.

Another object is to provide thermal-responsive means for automatically controlling operation of. one or more transmission speed ratio drives without thereby affecting operation of one or more additional drives. In connection with this object, in one embodiment thereof, the driver may manually invoke one or more transmission drives while other drives of an automatic nature are under control of the thermal-responsive means.

Another object is to provide -a simple and effective means forguarding against the possibility of .the transmission mechanism functioning to ground out the engine ignition system longer conditions for so controlling the transmission mechanism that it will not give rise to troublesome and objectionable performance.

Another object is to provide thermal-responsive means which will overrule or modify the action of the normal control mechanism at times when .mal control at other times.

' A further object is to. provide thermal-respon- I sive means for preventing operation of the torque-relieving means, such as ignition inter-.-

than a desired predetermined time.

Further objects and advantages of my'invention will be more apparent from the following illustrative embodiment thereof, reference being had to the accompanying drawings in which:

Fig. 1 is a side elevational view showing the motor vehicle engine and power transmission.

Fig. 2 is a longitudinal sectional elevational viewithrough the main clutching mechanism.

Fig. 3 is..a similar view through the change speed transmission. 7

Fig. 4 is a detail enlarged view of the blocker clutch. as seen in Fig. 3.

Fig. 5 is a sectional plan view illustrated as a development according to line 5-5 of Fig. 4, the automatic clutching sleeve being released.

Fig. 6 is a similar view showing the automatic clutching sleeve in its intermediate shift position during the drive blocking condtion. v Fig. 7 is a similar view showing the automatic clutching sleeve in its coasting relationship from the Fig. 6 showing, the clutching sleeve being unblocked during coast for its clutching movement.. Fig. 8 is a similar view showing the automati clutching sleeve in full clutching engagement.

Fig. 9 is a view similar to Fig. 5 but showing the automatic clutching sleeve in its other intermediate shift position during the coast blocking condition.

Fig. 10 is a diagrammatic view of the control I V mounted so that when remechanlsm for the automatic clutching sleeve, the latter being shown in its released position.-

Fig. 11 is a similar view of a portion of the Fig. control mechanism in another operating position.

Fig. 121s a detail sectional view showing the temperature responsive switch.

Fig. 13 is a view generally similar to Fig. 11

n In the drawings, A represents the internal com-'- bustion engine which drives through fluid coupling B and conventional type of friction main clutch C to the speed ratio transmission D whence the drive passes from output shaft 23 to drive the rear vehicle wheels in the usual manner.

The engine crankshaft 2i carries the vaned depressing pedal 23' in shifting into any one of these drives.

First is obtained by shifting sleeve 42 to clutch with teeth 43, the drive passing from engine A, through fluid coupling B, clutch C and shaft 21 to pinion28 thence through gear 34 and clutch E to countershaft 35. From the countershaft the drive is through gears 36, 39 and sleeve 42 to shaft 20.

Third is obtained by shifting sleeve 42 to clutch with teeth 44, the drive passing from the engine to the countershaft 35 as before,.thence through fluid coupling impeller 22 which in the well known manner drives the vaned runner 23 whence the drive passes through hub 24 to clutch driving ,member 25. This member then transmits the drive, when clutch C is engaged as in Fig. 2,

through driven member. to the transmission a driving shaft 21 carrying the main drive pinion 28. A clutch pedal 23 controls clutch C such that when the driver depresses this pedal, collar 30 is thrust forward to cause levers 3| to release the clutch driving pressure plate 32 against springs 33 thereby releasing the drive between runner 23 and shaft 21. The primary function of the main clutch C is to enable the driver to make manual shifts in transmission D. I, Referring to the transmission, pinion 28 is in constant mesh with gear 34 which drives countershaft 35 through an overrunning clutch E of the usual type such that when shaft 21 drives in its usual clockwise direction (looking from front to rear) then clutch E will engage to lock gear 34 to countershaft 35 whenever the gear 34 tends to drive faster than the countershaft. However,

whenever this gear 34 tends to rotate slower, than the countershaft then clutch E will automatically 21, under certain conditions,

release whereby shaft speed while countershaft 33 may readily drop its continues torevolve. V

Countershaft 45 comprises cluster gears 36, 31 and 38 which respectively provide drives in first, third and reverse. Freely rotatable on shaft 23 are the first and third driven gears 39 and 40 respectively in constant mesh with countershaft gears as and :1. A hub is splined on shaft 20 and-carries therewith a manually shlftable sleeve 42- adapted to shift from the Fig. 3 neutralposi tion either rearwardly to clutch with te th 143 of gear 39 or else forwardly to clutch with teeth 44 or gear 40. Sleeve 42 is operably connected to shift-rail. 45 adapted for operation by any suit- .7 ablemeans'under shifting control of the vehicle driver. r

' Shaft20 also carries reverse driven gear 49 fixed thereto. A reverse idler gear 41" is suitably erse drive is desired, idler 41 is shifted into'meshwith gears "and 46.

First, thirdandreverse speed ratio drives and neutral are under manual shift control of. the vehicle driver, the main clutch 0 being released by gears 31, 40 and sleeve 42 to shaft 20.

Reverse is obtained by shifting idler into mesh with gears 38, 45, sleeve 42 being in neutral, the reverse drive passing from the engine to the countershaft 35 as before, thence through gears 33, 41 and 43 to shaft 20.

v, Slidably splined on teeth 48 carried by gear 40 is the automatic clutch sleeve F which, under certain conditions, is adapted to shift forwardly to clutch with teeth 49 carried by pinion 28 thereby positively clutching shaft 21 directly to gear 40. This sleeve F is adapted to step-up the speed ratio drive from first to second and from third to fourth which is a direct drive speed ratio. Control means is provided which limits clutching of sleeve F to approximate synchronism with teeth 49 and alsoto a condition of engine coast, sleeve F being prevented from clutching during that condition known as engine drive as when the engine is being speeded up under power.

When driving in'fi'rst, second isobtained by the driver releasing the usual accelerator pedal 50 thereby allowing spring 5| to close the engine throttle valve and 'cause the engine to rapidly coast down. When this occurs, the engine along with shaft 21, pinion 23 and gear 34 all slow down while shaft 23 along with gears'39 and 36 continue their speeds by accommodation of clutch E now overruns. The engine slows down until teeth 49 are brought to approximate synchronism with sleeve F which thereupon automatically shifts to clutch with teeth 43 resulting in a two-way drive for second as follows: pinion 28 through sleeve F to gear 40 thence through gears 31, 36 and 33 to sleeve 42 and shaft 20, the clutch n overrunning.

0 accelerator pedal and resulting shift of sleeveF to clutch with teeth 49 when these parts are synchronized by reason of the engine. coasting down from the drive in third. The direct drive is a twoway drive as follows: pinion 28 throughsleeve F to gear 40 thence directly through sleeve 42 to-shaft 20, clutch E overrunning as before.

Referring. to Figs. 4 to 9 there is shown the blocking means forcontrolling clutching shift of sleeve F so as to limit clutching thereof to engine coasting and synchronous relationship of the clutchingparts. Sleeve F is provided with a series of pairs of what may be termed ,long' and I short teeth 52, 53 certain of which may be bridged or joined together. A biocker ring 54 is provided with blocking teeth 55 which either lie in .the path of forward shift of teeth 52 or 53 or elsebeg tween theseteeth to allow clutching shift of. sleeve F. Thus, blocker 54 has, at suitable locations, a drive lug 56 engaged inuaslot 51 of gear 40. The blocker is urged under, light energizing pressure of spring 53 into constant frictional-engagement "at 53 'with pinion 23 so that the blockertends to rotate with pinion .23 within the limits afiorded by the travel of lug 56 circumferentially in slot 51. During drive in first and third, the speed of shaft 21 exceeds the speed of gear 40 so that, if sleeve F is fully released, the parts will be positioned as in Fig. wherein the blocker teeth 55 are axially in alignment with the short teeth 53. If now the sleeve F is urged forwardly it will move to the Fig. 6 position of drive blocking and I duced to the speed of sleeve F slight further drop in speed of pinion 28 for a fraction of a revolution below the speed of sleeve F will cause blocker 54 to rotate slightly relative to sleeve F until blocker teeth 55 strike the adjacent sides of long teeth 52 as in Fig. 7 thereby limiting further reduction in speed of the blocker relative to sleeve F. At this time the sleeve F is free to complete its forward clutching shift with teeth 49, as in Fig. 8, the blocker teeth 55 passing between adjacent long and short teeth 52,53. With the sleeve F- thus clutched during engine coast, a two-way drive is established in second or fourth depending on whether the manually shiftable sleeve F was set for first or third just prior to the clutching shift of sleeve F.

In the event that sleeve F is urged forwardly from its Fig. 5 position at a time when the gear is rotating faster than pinion 28, then the blocker 54 will lag behind the sleeve and willbe blocked by engagement of long teeth 52 with the blocker teeth 55 as shown in Fig. 9. This is referred to as the coast blocking condition. If now the engine is speeded up by the driver depressing the accelerator pedal 58 in the usual manner, then the engine and blocker 54 rotate forwardly and blocker teeth 55 move over to the Fig. 6 drive blocking position thereby jumping the gap between teeth 52 and 53. This is the primary reason for providing the long and short teeth whereon the passengers and transmission mechanism.

On accelerating the engine from the Fig. 9 coast blocking condition 'the engine comes up to a speed limited by engagement of the overrunning clutch E for drive in either first or third depending on the setting of the manual shiftable sleeve 42. Then on releasing the accelerator pedal the sleeve F will synchronously clutch with teeth 49 during coast to'step-up the drive to either second or fourth as aforesaid.

The transmission is provided with suitable prime mover means for controlling shift of sleeve F along with several control means. R:ferring particularly to Figs. 10 and 11, there is illustrated a pressure fluid operated motor G utilizing air pressure for its operation. For convenience this motor is arranged to operate by the vacuum in the intake manifold system of the engine under control of electromagnetic means illustrated in the form of a solenoid H.

Forward shift of sleeve F is effected, under control of motor G, by reason of a spring 60 fixed at one end and exerting a pull on lever 6| which is 1 connected to sleeve F through the cross-shaft 82 cause the piston 68 and rod 18 to assume their Fig. llpo'sitions, latch 15 under action'of rattrap spring catches on the forward shoulder of detent l4 and holds the parts as in Fig. 11.

Latch 15 thus provides a releasable holding means for the rod 70. At this time rod portion moves further than rod 64 by the amount of gap 18, a stop 19 acting on lever t-H limiting forward movement of sleeve F by spring 80.

In order to provide for release of sleeve F, it is desirable to provide some means for momentarily relieving the torque load at the teeth 49 and sleeve F and in the present instance such means is provided as a system of grounding the primary terminal of the usual distributor of the ignition system whereby the engine ignition may be momentarily rendered ineffective thereby unloading the torque at sleeve F sufiiciently to insure its release by spring 69. This ignition interrupting system is under control of an interrupter switch H which is closed by'plunger 8|) and ball 8| whenever member 18 moves from its Fig. 11 position to its Fig. 10 position by reason of the enlarged rod portion between detents I3 and 12. The switch H comprises a conductor bridge piece 82. carried by'cup 83 which retains the spring seat 84 carried at the outer end of plunger 88. A spring 85 forms a yielding connection between cup 83 and seat 84' so that when ball 8| moves upwardly, the bridge piece 82 electrically connects the terminals of the switch H, the spring 85 yielding to accommodate any excess of movement ofthe ball beyond that required to engage the bridge piece 82 with the terminals. Ball 8| is prevented from falling inwardly beyond its position shown in Fig. 10 by reason of the in-turned seat 85 formed by peening the ball guide inwardly. A spring 81 yieldingly urges the assembly between bridge piece 82 and ball 8| inwardly to the Fig. 10 position .of these parts wherein switch H is open.

When the latch 15 is released, with the parts positioned as in Fig. 11, sleeve F being clutched, the spring 69 operates to move' member 10 rearwardly to close the gap 18 at the lost-motion between rod portion H and rod 64. This movement of rod 18 to its position establishing thrusttransmitting relationship with respect to follower rod 64 causes detent 13 to move ball 8| outwardly thereby closing switch H and grounding the ignition system. Ordinarily, when the ignition is thus interrupted, thereby relieving the thrustapplication at the teeth of sleeve F, spring 89 then causes further movement of rod 18 to thrust on rod 64 and release sleeve F. During this further movement of rod 18, which is usually practically continuous with its movement closing gap 18, the detent 12 is aligned with ball 8| so that spring 81 can act to open the switch H to restore the ignition system to itsnormal operation.

The vacuum supply to chamber 16 is under control of solenoid J which comprises an armature plunger 88 having valving parts 89, 98. In Fig. 10 the solenoid J is energized thereby raising plunger 88 against spring 9| to seat valve 98 and shut on the vacuum supply to chamber 16 and at the same time unseat valve 89 so as to vent this chamber through passage 92', chamber 98 and vent passage 94. When the solenoid is deenergized then spring 9| lowers plunger 88 thereby seating valve 88 to shut off vent and open valve 90 as in Fig. 11 thereby opening chamber I6 to the engine intake manifold K through passage 82, chambers 93 and as, and pipe 96.

A certain lost motion is provided between plunger 88 and the inwardly bent finger 91, of latch I5 so that when the plunger moves downwardly the latch may subsequently catch at detent I4 when vacuum operates piston 58, the parts then remaining in the Fig. 11 position independently of vacuum in chamber I6 until solenoid J is energized to release the latch and vent chamm. Lever m actuates a mm m which extends forwardly to adjust the engine throttle valve lever It is deemed preferable to provide a speed control on the energization of solenoid J so as to insure automatic release of sleeve F below a predetermined car speed and automatic engagement of sleeve F above a predetermined car speed. Whenever the car is in forward driving condition the manual sleeve 42 is either shifted rearwardly to the low range or forwardly to the high range I so that by drivinga governor from the counter-' shaft 35 it is possible to provide a speed control operated proportionate to the speed of travel 'of the car. Driven from'countershaft gear 98 is a governor L of any suitable type, this overnor operating a sleeve 99 outwardly along its drive shaft I as the car speed reaches a predetermined point, the break-away being under control of a detent' IOI if desired.

The sleeve 99 has a shoulder I02 engaged by the swinging switch piece I03 of the governor switch M. When the car is stationary the detent IOI is engaged and switch M is closed. As the car accelerates the governor eventually reaches its critical speed anddetent IOI releases thereby causing switch M to open. As the car slows down, the governor spring I04 restores the parts to the Fig. I0 position and by proportioning the various parts it is obvious that switch M may be made to function at desired speeds proportionate to car travel. As an example of one arrangement of governor operation and gearing arrangement, the governor may be made to open switch M during car accelerationin first and third respectively at approximately 'I and 15 M. P. H. (miles per hour), the switch M closing on stopping the car in direct and second at approximately 7 and 3 M. P. H. respectively.

The driver operated ignition switch is designated at N and comprises a conductor I05 which,

in the Fig. position showing the switch on -or closed, electrically connectscontacts I06 and I0'I.v Contact I06extends by conductor I08 to ammeter I09 and thence by conductor I I 0 to the usual storage'battery III and thence to ground II2. Contact I0'I has a conductor H3 extending therefrom to the engine ignition system herein shown in part as comprising coil II4 anddistributor 0 having a primary terminal HE.

A second conductor IIB extends from contact \IIII to the windings of solenoid J- and theme by conductor H1, H8 to one. terminal of ignition interrupter switch H, the other terminal extend;

' ing by a grounding conductor I I9 to the primary terminal IIS: of the distributor O.

Extendingv from conductor II! is a conductor I which'branches atconduetors HI and I22,

the former extending to governor switch M and thence to ground-I28. Conductor I22 extends to'kickdown switch P and thencethrough this swit'ch to ground I24. The switch P is normally open and is closed preferably by a full depression I of'accelerator pedal'50 acting through link I25 and a-bell crank lever I28 pivotally mounted at 7 second delayed until engine coast thereby enabling. drive I29. Whenpedal is thus depressed, the lever fourth to third or from second to first by energizingthe solenoid J.

The governor solenoid circuit is as follows: ground II2 to battery III thence by conductor I I0 to ammeter I09 and by conductor I08 to ignition switch N. From switch N this circuit extends through conductor I I6 and solenoid J and thence by conductors II'I, I20 and I2I to switch M and ground I23.

The kickdown solenoid circuit is the same as the governor solenoid circuit to conductor I20 whence this circuit extends by conductor I22 to kickdown switch P and ground I24.

The engine ignition circuit is the same as the governor solenoid circuit up to the ignition switch N whence this circuit extends by conductor II3 to coil H4 and distributor O.

The ignition grounding circuit under control of interrupter switch H extends from the primary terminal I I5 of the distributor 0 through conductor I I9 to interrupter switch H. From switch H this grounding circuit extends through conductor H8 and thence to a suitable ground. In the illustrated arrangement this ground-is provided either at I24 through conductors I20, I22 and 'kickdown switch P or else at I23 through conductors I20; I2I and governor switch M.

In the operation of the mechanism, the car at standstill and with the ignition switch N closed and the engine idling will cause the solenoid J to be energized as in Fig. 10 because governor switch M is closed thereby establishing the governor solenoid circuit. Cylinder I8 is vented and sleeve F disengaged as in Fig. 10. The driver shifts sleeve'42 to either the high or low range and accelerates the car ordinarily above the critical speed of governor L thereby causing switch M to open to break the governor solenoid circuit. As vacuum builds up in the engine intake manifold K, plunger 88 now being lowered by spring 9| because switch M is open, piston 68 will be operated byvacuum thereby moving member 'I0-to its'Fig. 11 latched position, rod portion "II moving forwardly beyond rod 64 because sleeve F is blocked against 'forward clutching movement with teeth. 49. As soon as the driver allows the engine to coast, sleeve F will engage teeth 49 synchronously, to step-up the drive .to either 'or fourth although the step-up will be in the slower driving ratio of first or third as long as desired. When sleeve F thus clutches,

rod moves to its Fig. 11 position. Ifthe car is initially accelerated in first above the governor critical speed and the engine allowed to coast, then second will automatically become operative.

forwardly to the high range, third will of course Then if the driver shifts sleeve 42 be skipped and fourth will be obtained because sleeve F will remain engaged. Ordinarily, especiallywhere the car is equipped with a fluid coupling B, the sleeve 42 may be left in its high range and all starts" and stops made without further shifting.- This is possible owing to slippage in the fluid coupling when stopping thecar for atraflic light and is practicable because the fluid coupling allows high engine torque for favorable car acceleration andbecause governor L directs a sion of the accelerator pedal will cause the transmission to step-down to third or first, the transmission step-up back to fourth or second taking place on release of the accelerator pedal with attendant synchronization of sleeve F with teeth 49.

When the accelerator pedal is fully depressed for the kickdown, above the car speed which opens switch M, switch P closes thereby energizing the kickdown solenoid circuit and causing solenoid J to raise plunger 88 and release latch thereby venting chamber 16. At this time the sleeve F is under driving torque from the engine operating under wide openthrottle. However, when latch 15 is released, spring 69 operates rod 10 rearwardly, sufliciently to close gap 18 thereby'closing the interrupter switch-H and causing the ignition grounding circuit to ground the engine ignition system. This relieves the torque at'sleeve F and spring 89 ordinarily operates as aforesaid to release the sleeve whereupon the ignition is restored at detent l2 and the engine quickly speeds upto engage overrunning clutch E for establishing the third or first driving ratio depending on the setting .of sleeve 42 prior to the kickdown operation.

On bringing the car to a stop when sleeve F is clutched as in'fourth, for example; the governor L closes governor switch M so as to energize solenoid J,- vent chamber 16 and cause release of sleeve F so that the car will be started in third,

- assuming the manual sleeve 42 to be left in its forward high range shift position.

The operation of the transmission mechanism as described is what may be termed the normal operation. However when the car has been left standing, as inover night parking, when the temperature is very cold such as below 10 or 15 Fahrenheit and especially around F. below zero, there is a tendency for the parts to become sluggish in operation and to bind at the various joints and bearings. After the engine has been running and the car operated for about five or ten minutes, the various parts warm up from an assumed -20 F. to around-10 or 15 F. above zero and the mechanism will then function as intended. The foregoing temperatures and warm-up time areofcourse given to illustrate the general conditions and these figures will, of course, widely vary according to climatic conditions and the type of transmission and control parts dealt with.

Under cold starting conditions the power of the vacuum is often strong enough, after driving in first or third above the critical speed of governor switch M, to cause the piston 68 to move to its Fig. 11 position to allow the sleeve F to clutch but then on stopping the car or attempting kickdown the rod 10 tends to fail to release the sleeve F. This accommodates movement of rod II! to take up gap 18 and ground the ignition with or without partial releasing movement of sleeve F. In either event the ignition is not restored and sometimes rod 10 sticks 50 that the car cannot be driven or even started. It is furthermore undesirable to allow the car to stop with the sleeve F clutched, as where it sticks under very cold conditions, because if the car is then on a hill tending to coast backwards and with sleeve 42 clutched with either teeth 43 or 44, the coast load will impose an attempted double drive through the transmission thereby preventing manual shift of sleeve 42. Then with the engine deael by reason of the grounded ignition, the car requires towing before the parts can be restored to proper relationship. The double drive, for example, is as follows, assuming sleeve 42 to be clutched with teeth 44 and sleeve F clutched with teeth 49. One attempted drive, when the car coasts backwards, is from shaft 20 and hub 4i through sleeve 42 to gear 40 and thence through sleeve F to pinion 28. The other attempted drive is from gear 40 to countershaft gear 31 through clutch E and gear 34 to pinion 28. As these drives are I of different ratio the transmission locks-up or is subjected to what is called an undesired noback condition.

In order to overcome the foregoing difiiculties, I have provided temperature responsive means so arranged in conjunction with the transmission mechanism that it cannot improperly function under the relatively cold conditions. By preference, when the transmision embodies a manual shift as at sleeve 42 in addition to an automatic or power controlled shift as at sleeve F, I arrange the temperature control so that it will act on the automatic shift control without thereby affecting the manual shift.

In oneembodiment of my invention illustrated in Figs. 10 and 11, I arrange the'temperature control so that it will prevent the'device G from operating under cold conditions of the mechanism, the device G being rendered operative automatically upon the mechanismwarming up to a temperature whichinsures its proper operation.

Under such conditions, after overnight cold parking, the sleeve 42 may be shifted and the car driven in first, third or reverse but sleeve F will remain in its Figs. 3 and 10 position of release until the parts have sufliciently warmed up.

In another embodiment of my invention illustrated in Fig. 13, I arrang my temperature control so that, under the cold conditions aforesaid, the torque-relieving means cannot be operated. With this arrangement, when ignition grounding is employed as the torque-relieving means, the engine cannot be rendered dead and even if sleeve F should remain clutched on stoppin Or if gap I8 should be taken up to close the interrupter switch H without attendant release of the sleeve and opening of switch H, the engine can be driven and the no-back condition overcome or the car can be started and driven with sleeve F clutched. After the parts have warmed up sufliciently then my temperature responsive means acts automatically to render the ignition interrupting means operative and the whole transmission system then operates normally.

Referring flrstto the Fig. 10 system, I have provided a temperature responsive switch Q, best shown in 12, so arranged that under the cold conditions it will always ground the grounding conductor I20 of solenoid J regardless of whether portant mechanism for consideration under the conditions dealt with, I preferably mount the switch Q on the outside wall of motor G as indicated in Figs. 1 and 12. switch is of standard make having a bi-metal conductor element I32 fixed at one end to a support I33 suitably grounded at I34 and having its other end formed with a terminal I35 shown in Fig. 12 as contacting with a fixed terminal Ill from which a conductor I31 extends to th conductor I". A guide I38 may be provided for the element I32.

' While the temperature responsive characteristicsot switch Q may widely varyaccording to a variety-of conditions dealt with, let it be assumed that switch Q is so arranged as that it will open at F. above zero and will close at temperatures below said 10 F. With such an arrangement the solenoid J will always be energized by grounding conductor I through switch Q whenever the temperature at the switch is below the assumed 10 F. When the car is then started, 'firstand third speeds are available but sleeve F will remain unclutched even when switch M opens or when switch P closes. Switch Q thus maintains sole- 20 noid J energized and the transmission control parts at motor G remain in their Fig. 10 positions. However, after the engine has been running and the car driven for a short while, the

motor G and switch Q rise in temperature suffl- 5 ciently to cause the bi-metal switch element I32 to swing contact. I35 away from contact I36 and thereby break the grounding circuit through switch Q. The transmission control system then operates normally until such time as the temperature at switch Q again falls enough to cause element I32 to move contact I35 into engagement with contact I36, as when the car is parked for a sufiicient period of time. Not onlywill the sleeve F be maintained in its released'position as long as switch Q is closed, but this switch also controls the motor G such that the interrupter switch H is rendered inoperative and the ignition system cannot be interrupted at the grounding conduit H8.

In the Fig. 13 embodiment, I interpose a temwhen starting the car under cold conditions;

switch Q is open making it impossibleto interrupt the ignition through grounding conductor I 19 even though the interrupter switch H is closed and gap 18 is taken up, this beingthe condition illustrated in Fig. l3. This cannot give rise to a.

- the aforesaid objections because even though 'sleeveF-does not release, ,the engine can still operate normally and-sleeve. 42 can be disengaged under theaioresaidno-back conditions because forward drive torque can-be applied iromthe en aim: to sleeve soas to overcome the coast torque. As soon asi-switch Q. closes, incident to the brief warm-upperiod; then the ignition inter- H g v rupting means is thereby'rendered operativeand temperature variation.

the onsystem-williunction norir ally.v y 3 Referring to-Fig. -.14- the;SW1tchiP0int;0r: terminal iflis insulated at llltirom the fol-metal 1 132.. -In thismangment-theelectnca current 7 A I g g I, *tmvelflmhwmtm 9 fin aexcep 10 en ine tothe vehicle; driver operable m an for that the'circuitsoeairom i ll --=m;-m and' thence directlmto. ground iii-rm "steadot going througlrthebi-metal'ill. iThish the advantage thatthe bi-.-m etal ,is not-heated vby the o current and bere orevdaesp 40 perature responsive switch Q in the grounding influence operation of switch Q. Obviously the Fig. 14 arrangement may, it'desired, be incorporated in the Fig. 13 embodiment by arranging the grounding circuit directly from conductor III to terminal l3lso as not to pass through the bi- 7 0 means operableto effect change between two driving speed ratios from the engine toithe vehicle; and temperature responsive means for automatically rendering the atoresaid'means' selectively operative and inoperative to eflect said change in response to predetermined temperature variation.

2. In a motor vehicle drive having an engine;

a variable speed ratio transmission comprising a plurality of means operating respectively to control relatively different speed ratio drives be-- tween the engine and vehicle; and thermal-means for controlling operation of only one of said speed ratio control means.

3. In a motor vehicle drive having an engine: a variable speed ratio transmission comprising a plurality of means operating respectively to control relatively different speed ratio drives between the engine and vehicle: and temperature responsive means for rendering one of said speed ratio control means inoperative without thereby affecting operation of the remainder of said plurality of speed ratio control means.

4. In a motor vehicle drive having an engine; a variable speed ratio transmission comprising plurality jot means operating respectively to control relatively different speed ratio drives between the engine and vehicle; and temperature responsive means for automatically rendering one of said speed ratio control means selectively operative and inoperative in response to predetermined temperature variation without thereby affecting operation of the remainder of said plurality of speed ratio control means.

5. In a motor vehicle drive having an engine; a variable speed ratiotransmission having a, pair of means respectively operable to provide a pair of relatively diilerent speed ratio drives from the engine to the vehicle; driver operable means for eii'ecting operation of one of said pairoi speed ratio drive means; power means for controlling operation of the other of said pair of speed ratio drive means; and temperature responsivemeans for controllingsaid power means, 6. In a motor vehicle drive having anengine;

"a variable speed ratio transmission having a pair or means respectively operable to provide a'pair of relatively different speed ratio drives from the engine to the vehicle; driver operable means ior eilecting operation clone of said pair or speed ratio drive means; power means 'iorcontrolling operation ofthe other of saidpair oi speed'ratio drive means; and temperature responsive means for rendering said power meansv selectively inoperative, and operative in response to predeter- '7. In' amoto' vehicle driv'e having an engine;

a variable speed ratio transmission Va'pair of m v V respectively operable to provide sites of relatively diiiferent speedratio drives i'ror'n' the .eg b ihsgo erati n o 9: Isaidi P3 1 ratio dr ve ans: pow e lio dntiouinz' 1. 2 i deri 'e. sgidlr w f m an fm a v hout thereby affecting operation of said driver opf erable means.

8. In a motor vehicle drive having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle; driver operable means for efiecting operation of said transmission mechanism thereby to provide or release said drive; transmission mechanism operable to provide another drive from the engine to the vehicle, comprising, positively engageable drive-control elements one of which is movable into engaging relationship with the other to accommodate said other drive and into disengaging relationship with respect to said other element to release said other drive; and temperature responsive means for controlling operation of the second said transmission mechanism without thereby affecting said operation of the first said transmission mechanism by said driver operable means.

9. In a motor vehicle drive having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle; driver operable means for effecting operation of said transmission mechanism thereby to provide or release said drive; transmission mechanism operable to provide another drive from the engine to the vehicle, comprising, positively engageable drivecontrol elements one of which is movable into engaging relationship with the other to accommodate said oth r drive and into disengaging relationship with respect to said other element to release said other drive; means operable -to control movement of said movable element between vits 'said positions of engaging and disengaging relationship; and temperature responsive means for controlling operation of said movement-control-means without thereby afiecting said operation of the first said transmission mechanism by said driver operable means.

10. In a motor vehicle drive having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle; driver operable means for effecting operation of said transmission mechanism thereby to provide or release said drive; transmission mechanism operable to provide another drive from the engine to the vehicle, comprising, positively engageable drivecontrol elements one of which is movable into engaging relationship with the other to accommodate said other drive and into disengaging relationship with respect to said other element to release said other drive; means operable to control movement of said movable element from its said position of disengaging relationship to its said position of engaging relationship; and temperature responsive means for controlling operation of said movement-control-means so as to selectively render the same operative and inoperative in response to' predetermined temperature change without thereby affecting said operation of the first said transmission mechanism by said driver operable means.

11. In amotor vehicle drive having an engine: transmission mechanism operable to provide a drive from the engine to the vehicle, said mechanism including engageable drive-control elements one of which is movable into engaging re-' lationship with the other to accommodate said drive and into disengaging relationship with respect tosaid'otherelement to release said drive;

pressure differential means operable to control movement of said movable element; and temperature responsive means for controlling operation 1 of said pressure differential means so as to selectively render the same operative or inoperative.

12. In a motor vehicle drive having an engine: transmission mechanism operable to .provide a drive from the engine to the vehicle, said mechanism including engageable drive-control elements one of which is movable into engaging relationship with the other to accommodate said drive and into disengaging relationship with respect to said other element to release said drive; means comprising a vacuum motor operable to control movement of said movable element; and temperature responsive means for controlling application of vacuum to said motor so as to selectively render said movement-'control means operative and. inoperative in response to predetermined temperature change. 7

13. In a motor vehicle drive having an engine; transmission mechanism operable to provide a drive from'the engine to the vehicle, said mechanism including engageable drive-control ele=- ments one of which is movable into engaging relationship with the other to accommodate said drive and into disengaging relationship with respect to said other element to release said drive; a pressure fluid motor operable to control movement of said movable element from its said position of disengaging relationship to its said position of engaging relationship; solenoid controlled valving means for controlling application of pressure fluid to said motor; and temperature responsive means for controlling energization of said solenoid so as to selectively render said motor operative and inoperative in response to predetermined temperature change.

14. In a drive for amotor vehicle having an engine; transmission mechanism operable to pro.- vide a drive from the engine to the vehicle, said mechanism including positively engageable driveduring said drive so as to resist relative disengagement thereof .to release said drive until said thrust-application is relieved, means operable upon relief of said thrust-application for efiecting said relative disengagement of said elements; means for efiecting relief of said thrust-application; and means operating in response to temperature ambient to said element-disengaging-means for controlling said relief-.eiiecting-means.

15. In a drive for a motor vehicle having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle, said mechanism including positively engageable drivecontrol elements one of which is movable into engaging relationship with the other to accommodate said drive and into disengaging relation- ,ship with respect to said other element to release said drive, said elements when relatively engaged being subject to thrust-application therebetween during said drive so as to resist relative disengagement thereof to release said drive until said thrust-application is relieved; means operable upon relief of said thrust-application for efl'ect-v ing said relative disengagement of said elements; means for efiecting relief of said thrust-application; and temperature responsive means for automatically rendering said relief-eflecting-means selectively operative and inoperative to relieve -said thrust-application in response to predetermined variation of temperature ambient with respect to said element-disengaging-means.

- for said engine adapted to be interrupted to resaid elementfdisengaging-means, I V t 18. In a drive for a motor vehicle having an engaging relationship with; theotherv to accom- 16. In a drive for a motor vehicle having an engine; transmission mechanism operable to provide a drive from the engineto the vehicle, said mechanism including'positively engageable drivecontrol elements one of which is movable into 6 engaging relationship with the other to. accom-- modate said drive and into" disengaging relationship with respect to said other element to release said drive, said elements when relatively engaged being subject to thrust-application therebetween during said drive so as to resist .relativedisengagement thereof to release said drive until said thrust-application is relieved; an ignition system for said engine adapted; to be interrupted to relievesaid thrust-application; means operable upon interruption of said ignition system for effecting saidrelative vdisengagement of salt elements; means for interrupting said ignition system; and means responsiv'eto temperature ambient to said element-disengaging-means. for con- 20 trolling said interrupting means.

l7.In a drive fora motor vehicle having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle, said mechanism including positively engageable'drivecontrol elements one of whichis movable into engaging relationship with the other to accommodate said driveand into disengaging relationship with respect to said other element to release said drive, said elements when relatively engaged being subject to thrust-application therebetween during said drive so its to resist relative disengagement thereof to release said drive until said thrust application is relieved; an ignition system lieve said thrust-application; means operable upon interruption of said ignition system for ef fecting said relative disengagement of saidelements; means for 'interrupting'said ignition system; and temperature responsive means for automatically rendering said interrupting means vselectively operable and inoperable to interrupt said ignition system ,in response to predetermined variation of temperature ambient with re'spectto engine; transmission mechanism operable to provide a drivefrom the engine to the vehicle, said mechanism including,positively engageable' drive- 5" control elementshone Ofwhich is movablev intomodate said drive and into, disengaging relation assaeio gagement thereof to release said drive until said thrust-application is relieved; an ignition system for said engineadapted to be interrupted to relieve said thrust application; means for intera variable speed ratio transmission comprising a plurality of means operating respectively to con- -trol relatively difierent speed ratio drives between the engine and vehicle; an ignition system for said engine adapted to be interrupted to facilitate operation of one of said speed ratio control means; means for interrupting said ignition system; and temperature responsive means for controlling said interrupting means so as to render said one speed ratio control means selectively operative and inoperative in response to predetermined temperature change without thereby affecting operation of the remainder of said plurality of speed ratio control means.

. 21. In a drive for a motor vehicle having an engine; transmission mechanism operable to provide a drive from the engine to the vehicle, said mechanism including positively engageable drive-control elements one of which is movable into 'engagingrelationship with the other to accommodaie said drive and into disengaging relationship with respect to said pther element to release said drive, said elements when relatively engaged being subject to thrust-application therebetween during said drive so as to resist relative disengagement thereof to release said drive until said thrust application is. relieved; means for effecting relief of said thrust-application; means operable to control movement of said movableelement; transmission mechanism operable to provide another drive from the engine to the vehicle; driver operable means for efiecting operation of the second said transmission mechanism thereby to provide or release said other drive; and temperature responsive means for controlling said relief-effecting-means and said vmovement-control-means in response to predetermined temperature change without thereby aflecting operation of the second said transmissionmechanism by said driver operable means.

22. In a motor vehicle drive having an'engine provided with, a ignition system adapted to be interrupted; vmeans for grounding said ignition 3 system} thereby to interrupt said i'gnition system; a variable speed ratio transmission com prising meansloperable, as an incident to inter- ,ruptionpf saidjignition] system for effecting changeIin the speed ratio drive between the engine. and .ivehicle; andja thermal-responsive t o o o n saidgrounding meansso asgt'o'selectively render the samejoperativ'e or in- "Lemme tolinterrupt in p nse topredetcrmin' edchag ar ram d "w Pet r veh cl are said electrically energizable device; and temperature responsive means for controlling energization of said electrically energizable device independently of said switch such that said motor means is rendered inoperative when the temperature of said motor means falls below a predetermined value which is less than the freezing point.

-24. In a motor vehicle drive having an engine provided with a throttle; a variable speed ratio transmission comprising means operable to effect change in the speed ratio drive between the en- Y gine and vehicle; motor means including an electrically energizable device for controlling operation of said speed ratio change means; a switch adapted to be opened and closed to control energization of said electrically energizable device; temperature responsive means for controlling energization of said electrically energizable device as a function of the temperature of said motor means and independently of said switch; and means operable under control of the vehicle driver for adjusting said throttle and operating said switch.

25. In a motor vehicle drive having an engine; a variable speed ratio transmission comprising means operable to effect change in the speed ratio drive between the engine and vehicle; motor means including an electrically energizable device for controlling operation of said speed ratio change means; a switch adapted to be opened and closed to control energization of said elecelectrically energizable device as a function of the temperature of said motor means and independently of said switch; and means operable in response to predetermined vehicle driving speed for operating said switch.

26. In a motor vehicle having an engine; a variable speed ratio transmission; a motor normally operable to control said transmission to effect change in the speed ratio drive between the engine and vehicle, said motor being of a type susceptible tofaulty operation after'the vehicle has been parked overnight under conditions exposing said motor to atmospheric temperatures below the freezing point; means for mountin said motor so as to receive heat generated by said engine such that, when the vehicle has been subjected to the aforesaid parking conditions, susceptibility to faulty operation of said motor is overcome owing to temperature rise of trically energizable device; temperature responsive means for controlling energization of said said motor after the engine has been operated over a period of time; and temperature responsive means carried by the vehicle so as to be subjected to heat generated by the engine, said temperature responsive means operating automatically to render said motor inoperative when the temperature of said motor falls below a predetermined value less than the freezing point when the vehicle has been subjected to the aforesaid parking conditions, and to restore said motor for the aforesaid normal operation thereof after the engine has been operated over the aforesaid period of time.

IAN C. MCKECHNIE. 

